Road building machine with two adjustable work implements

ABSTRACT

A road building machine having the general form of a motor grader having a blade mounted from a circle support for adjustment and having specifically a scarifier mounted from the same circle support enabling similar adjustment and control thereof.

United States Patent Gurries et al.

1451 Apr. 29, 1975 [5 ROAD BUILDING MACHINE WITH TWO 2.197.549 4/1940 Hargrave ct al. 172/784 x ADJUSTABLE WORK IMPLEMENTS 2.243.251 5/l94l Gustafson 37/DlG. 3 2.686.982 8/[954 Leliter 172/784 [75] Inventors: Raymond A. Curries: Burnett J. 2.799.099 7/1957 Lcliter 1 172/795 X Christensen. both of San Jose. Calif. 3.274.713 9/1966 Jones l 172/197 3.430.703 3/1969 Riche' 37/l 17.5 X [73] cmpm'amn'oklahmm OW 3.444.936 5/1969 Page 5131. 172/795 Oklfl- 3.465.829 9/1969 Fisher et a]. 172/793 x 1221 FOREIGN PATENTS OR APPLICATIONS PP N921 243-098 69.068 3/1930 Sweden 2 172 734 Related US. Application Data [631 Continuation (If Ser. N111 114.3411. Feb. 10. 1971. 51311" abandoned. which is a continuation of Scr. No. H1" E-w"1ifl rE-H-EiCkhO|l 780.816. Dec. 3. 1968. abandoned. Attorney, Agent. or FirmPaul B. Fihe 152] US. Cl. 172/784; 37/DIG. l2. l72/743 51 int. c1 E02f 3/12 1571 ABSTRACT [58] Fleld of Search 37/DIG- A road building machine having the general form of a 74l 743- motor grader having a blade mounted from a circle 97-199 support for adjustment and having specifically a scarifier mounted from the same circle support enabling [56] References cued similar adjustment and control thereof.

UNITED STATES PATENTS 2,062,544 12/1931 Weeks 172/795 x 2 5 Draw figures O r I I 0 I I/ I I O 78 I' 12s,

1 l p L o 2 il 25.

1 11 c' ir 9;) 72 I04 Z 114 n 1 80 I I H6 1 1 D bu H h I06 112 I 76 30 FAYENTEDAFRZSIWS SHEET 10F 3 INVENTOR. RAYMOND A. GURRIES BURNETT J. CHRISTENSEI BY PLTENTED N B B 3.880.243

SHEEI 2 BF 3 INVENTOR RAYMOND A.GURRIES BURNETT J. CHRISTENSEF PATENIEDAPR29|Q75 3.880.243

SHEET 3 OF 3 W ENTOR. RAYMOND A.GURRIES BURNETT J. CHR'STENSEN ROAD BUILDING MACHINE WITH TWO ADJUSTABLE WORK IMPLEMENTS This application is a continuation of co-pending application Ser. No. ll4,348 filed Feb. ll), l97l. now abandoned. which in turn is a continuation of copending application Ser. No. 780,816, filed Dec. 3. I968. and now abandoned.

The present invention relates generally to road building machines and, more particularly. to a road building machine including two or more distinct working implements which can alternatively be brought into operation to enhance the overall utility of the machine.

BACKGROUND OF THE INVENTION Conventional motor graders. which have been used for some time in road building operations. each include a mobile self-propelled frame from which at least one working implement is adjustably suspended, such implement normally taking the form of a scraper blade which is supported from the frame, both for height and cross-slope adjustment. Most commonly the scraper blade is supported from a circle enabling angular ad justment of the blade about a substantially vertical axis, and the circle. in turn, is supported at the rear end of a drawbar whose forward end is joined to the frame by a universal joint which enables the entire circle and the blade supported therefrom to be raised or lowered or to be varied in its transverse slope about a horizontal longitudinally extending axis. Rather recently, automatic control mechanisms have been incorporated on motor grader including a pendulum-actuated sensing mechanism for determining and controlling the blade cross-slope and an exterior reference sensing mecha nism for controlling the blade height. as shown by way of example in U.S. Pat. No. 3.346.976. issued to John Curlett et al. on Oct. 17. 1967.

Some motor graders also mount a second working implement in the form of a scarifier from the mobile frame normally in advance of the scraper blade, as shown by way of example in U.S. Pat. No. 2.96l,783. and as shown in that Patent. separate control mechanisms are utilized for raising or lowering the scarifier between operative and inoperative positions. Conventionally, as in the lastmentioned patent. the disposition of the scarifier is manually controlled and. in practice. the scarifier teeth are normally positioned for operation slightly below the desired finished grade level wherefore it is incumbent upon the road builder to subsequently utilize another machine to recompact the earth after it has been scarified to assure the existence of a firm earth base for the finished roadway. The obvious result is a considerable increase in the overall cost of the road building operation.

SUMMARY OF THE INVENTION It is a general objective of the present invention to provide a road building machine wherein two or more working implements can be mounted from a single adjustable. and preferably automatically controlled, support and alternatively brought into operation, thus to render the machine less expensive but at the same time more effective in its overall utilization. Generally, the objective is achieved by providing a road building machine which includes an adjustable support for a firstworking implement, such as the scraper blade of a motor grader, wherein such support incorporates con trol mechanisms for varying the disposition of such blade, in accordance with particular requirements. The same adjustable support. in turn. mounts a secondworking implement, which may, for example. constitute a scarifier unit. enabling the latter to be moved between operative and inoperative positions and providing for adjustable control of such scarifier or other working implement when in its operative position.

If the machine incorporates automatic control mechanisms. as exemplified by those in the afore-mentioned Curlett et al. U.S. Pat. No. 3,346,976, the elevation and cross-slope of the scarifier can be controlled in precisely the same fashion that the scraper blade is normally controlled but, of course. without the addition of any separate automatic control mechanism.

When the working implement, such as the scarifier. is operating, it is, of course. well-known that it encounters various resistance to motion, depending upon the character of the earth encountered by its teeth so that in accordance with an additional aspect of the present invention. the support for the alternatively operable working implements embodies some form of clamping mechanism or the like to assure rigidity and precision in the operation of either implement. If the working implements specifically take the form of a scraper blade and a scarifier unit mounted from a circle, as in the case of a conventional motor grader, such rigid clamping mechanism preferably takes the form of that disclosed in the pending application ofRaymond A. Gurries. Ser. No. 635.]94, entitled. CLAMPING MECH- ANISM FOR ROAD BUILDING MACHINES OR THE LIKE." By incorporating such a mechanism, both the blade and the scarifier. during their alternate operation, are maintained at precisely controlled levels. thus to eliminate any necessity for subsequent refilling and compacting operations.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing summary of a road building machine embodying the present invention will be more readily understood by reference to the following detailed description of the exemplary structure shown in the accompanying drawings wherein:

FIG. 1 is a side elevational view of a road grader embodying the invention.

FIG. 2 is a fragmentary bottom plan view as taken along line 2-2 of FIG. 1 illustrating one portion of the implement supporting structure,

FIG. 3 is a fragmentary sectional view taken along line 3-3 of FIG. 2,

FIG. 4 is an enlarged side elevational view of the scraper blade, scarifier and associated supporting structure therefor. and

FIG. 5 is a fragmentary top plan view of such supporting structure substantially as viewed along line 5-5 of FIG. I.

DESCRIPTION OF THE PREFERRED EMBODIMENT With initial reference to FIG. 1, the road grader. em

bodying the present invention. is of generally convensteered about vertical pivot axes through suitable interconnecting linkage to a steering wheel 19 mounted above the rear portion of the frame in front of an operator's seat 20.

An auxiliary blade-mounting frame 22, commonly referred to as a drawbar, is adjustably mounted below the arched portion of the main frame and. in turn, supports the scraper blade 30 and scarifier unit 32 thereunder for additional adjustments, as will become apparent hereinafter. More particularly. the drawbar 22 is secured by a universal pivotal mount 24 to the front of the main frame 10 and extends rearwardly therefrom in a generally triangular configuration. On opposite sides of its rearward end, the drawbar 22 is pivotally secured to the lower end of adjustment-links 34 which are, in turn, pivotally secured at their upper end to crank arms 36 which can be turned from suitable actuating linkage 38 under the control of operator so that the drawbar can be raised or lowered and thus, in turn, effect raising or lowering of the blade 30 and scarifier 32 suspended therefrom. Preferably, as illustrated, one ofthe connecting links 34 takes the form of a hydraulic ram which can be extended or retracted thus to vary the transverse disposition of the drawbar 22 and, consequently, the cross-slope of the blade 30 and scarifier 32 suspended therefrom. The extension or retraction of the ram is under the control of a pendulum controlled valve-actuating mechanism 102 and feedback linkage H0 is connected between the drawbar 22 and the pendulum controlled mechanism 102 to indicate when a desired transverse slope of the blade 30 or scarifier 32 has been obtained. This structure is that described in detail in U.S. Pat. No. 3,346,976, to which reference is made for details of the structure and the manner of operation.

To enable angular adjustment of the blade 30 and scarifier 32 about a vertical axis, an open ring or circle 26 is supported for rotation under the rear portion of the drawbar 22. More particularly, a plurality of C- shaped circle-supporting brackets 28 are integrally formed below the drawbar, as best shown in FIGS. 2 and 3, the circle 26 being adapted to rest on the lower leg portion of the C-shaped brackets for sliding movement about its own central axis. The sides of the C- shaped brackets 28 laterally confine the circle 26 and the tops of the C-shaped brackets are slightly spaced from the top of the circle so as to limit the amount of permissible lifting or vertical motion of the circle. To effect the desired rotation of the circle 26, its interior is formed with a plurality of inwardly projecting teeth so as to form an internal ring gear 33, which is arranged to mesh with a gear 34 on the shaft 36 of a suitable hydraulic motor 38 which is under the operators control, such arrangement being conventional.

Since in normal operation of the road grader, various forces are transmitted to the blade 30 or scarifier 32, such forces are obviously transmitted also to the supporting circle 26 tending to effect continual slight vibrational shifting movement thereof within the slidable supporting brackets 28. Considerable wear is therefore experienced and is accelerated by the obvious presence of dirt and small rocks between the supporting brackets and the supported circle.

To preclude such shifting movement of the circle 26 and the consequent wear, means are provided in accor dance with the present invention to clamp the circle 26 rigidly in position on the drawbar 22 once an adjusted position of the circle has been obtained. More particularly, and with continued reference to FIGS. 2 and 3, a plurality of clamping levers 40 are supported under the drawbar to effect the desired rigid clamping engagement between the circle 26 and the drawbar 22, one of such levers 40 being illustrated most clearly in FIG. 3. As there shown, the lever 40 is supported a short distance from its outer end on a pivot pin 42 carried by brackets 44 depending from the under surface of the drawbar 22. When so pivotally supported the outer extremity of the lever 40 underlies the inwardly projecting ring gear portion of the circle 26, so as to be capable upon pivotal movement of the lever 40 in a clockwise direction from the position shown in FIG. 3, to urge the circle 26 upwardly into clamping engagement with the upper leg of the C-shaped bracket 28. The other end of the lever 40 is considerably longer and, at its extremity, is pivotally connected to the lower end of a hydraulic ram 46 which, in turn, is pivotally mounted on the drawbar 22 thereabove so that upon extension of the ram the lever 40 is brought into clamping engagement with the circle 26, and upon its retraction, the lever 40 is withdrawn sufficiently to permit the circle to drop onto the lower portion of the C-shaped bracket 28 so as to be capable of sliding rotary movement thereon. Preferably four of the levers 40 are employed to provide a balance clamped engagement with the circle 26 and, accordingly, four hydraulic rams, two of which are indicated at 46 in FIG. 2, are energized simultaneously through suitable hydraulic conduits under the control of suitable valves by the operator, as described in detail in the mentioned application of Raymond A. Gurries, Ser. No. 635,]94, entitled, CLAMPlNG MECHANISM FOR ROAD BUILDING MACHINES OR THE LIKE," to which reference is made for structural and operational details.

A pair of arms curve downwardly from the opposite sides of the described circle 26 and carry aligned stub shafts 72 at their lower extremities to provide pivotal support for blade-mounting brackets 74, one of which is best illustrated in FIGS. 4 and 5. At its forward edge, each bracket 74 carries a U-shaped seat 76 adjacent its lower end and an additional retainer 78 of inverted U-shaped configuration adjacent its upper end, the two U-shaped members being arranged to confine therebetween a pair of parallel rails 80, 82 rigidly secured to the rear face of the curved grading blade 30 itself. The lower rail 80 normally rests slidably on the U-shaped seat 76 and the upper rail 82 is spaced slightly from the bottom of the inverted Ushaped re tainer 78, thus to enable slidable shifting movement of the blade on the supporting brackets. In order to effect such slidable movement, a hydraulic ram 74 is disposed longitudinally of the blade 30 behind its rear face and is connected at one end to one of the brackets 74 and its opposite end to the blade 30 itself so that extension of the ram will provide movement of the blade in one direction, and retraction thereof will, of course, provide for lateral shifting movement of the blade in the opposite direction. The described slidable mount for the blade 30 and the hydraulic mechanism for actuating the same is conventional and will, accordingly, be described in no further detail.

The brackets 74, the blade 30 supported therefrom and the hydraulic ram 84 are arranged for limited pivotal motion about the axis defined by the stub shafts 72 on the mounting arms 70 to enable a variation in the angle of blade engagement with the earth. For this purpose, hydraulic rams 86 are connected between the opposite sides of the circle 26 and the pivoted mounting brackets 74 and are arranged, again, in a conventional fashion for hydraulic extension or retraction under the control of the operator.

An additional clamping mechanism is provided to secure the blade 30 rigidly in its laterally adjusted position after such adjustment has been made by relative sliding movement of the blade supporting rails 80. 82 along the U-shaped seat 76 at the lower end of the supporting brackets 74. With continued reference to FIGS. 4 and 5, such clamping mechanism takes the form preferably of a simple lever 90 which is centrally mounted on the same pivot shaft 72 that mounts the blade supporting brackets 74, one end of the lever 90 extending forwardly therefrom so as to underlie the lower supporting rail 80 and the other end extending a considerable distance angularly upwardly in the opposite direction for pivotal connection to one end of a hydraulic ram 92 whose opposite extremity is connected pivotally to the side of the supporting bracket 74. It will be understood that a similar lever and actuating ram is mounted on the bracket at the other side of the machine.

When the hydraulic rams 92 are extended, the levers 90 are caused to pivot in a counter-clockwise direction, as viewed in FIG. 4, so that the lower end of the lever 90 is moved upwardly into engagement with the lower rail 80 to thereafter lift the entire blade structure until the upper surface of the upper rail 82 is brought into clamped engagement with the under surface of the U- shaped retainer 78. Obviously, such clamped engagement will be released upon retraction of the hydraulic rams 92.

With continued reference to FIG. I and, more particularly, to FIGS. 4 and 5, the second working implement in the illustrated embodiment of the invention constitutes the mentioned scarifier unit 32 which is also mounted from the described circle 26 so as to partake of the same adjustments as the previously described blade structure 30. More particularly, a pair of additional mounting arms 100 are secured at their upper extremities rigidly as by welding to the rigid blademounting arms 70 and project downwardly and rearwardly therefrom, as can be best visualized with reference to FIG. 4. Only one of the scarifier supporting arms 100 is illustrated in FIG. 5, but it will be understood that the other is disposed in mirror symmetry at the opposite side of the circle 26 and the scarifiermounting structure associated with both arms 100 is substantially identical. wherefore the description of the mounting and adjustment arrangement on one side, as illustrated in FIGS. 4 and 5, will enable an understanding of the entire mounting arrangement for the scarifier 32.

At its lower extremity, each of the arms 100 carries a transverse pivot shaft 102 which on opposite sides of the arm mounts a pair of ears 104 which extend downwardly and are rigidly connected at their lower and forward ends to a transversely-extending beam 106 from which the individual scarifier teeth I08 are supported. More particularly, the individual teeth I08 are carried in forwardly and downwardly projecting dispositions at the lower ends of mounting shanks IIO whose upper ends are welded or otherwise secured to the beam 106. Preferably, as can be visualizedvbest by reference to FIG. 5, the disposition of the adjacent scarifier teeth 108 is staggered and the lateral spacing between the teeth is approximately 6 inches in accordance with conventional practice. Since the transverse beam 106 and the teeth 108 supported therefrom are mounted from the described pivot shaft 102, the lower portion of the unit is capable of pivoting from the operative full-line disposition, as shown in FIG. 4, to an inoperative raised disposition, shown in full lines in FIG. I and also indicated in phantom lines in FIG. 4. When the unit is moved to the operative position, shown in full lines in FIG. 4. the lower extremity of the teeth 108 lie at a level approximately 6 inches below the lower cutting edge of the blade 30 but when the unit is pivoted to its upper inoperative disposition, the lowermost portion of the scarifier 32 lies 3 or 4 inches above the lower edge of the cutting blade 30, thus enabling alternate use of the blade or the scarifier teeth, as required.

In order to effect the described pivotal motion of the teeth 108 between their operative and inoperative dispositions, a short bracket 112 extends forwardly from the transverse beam 106 and is provided with an opening that loosely receives a pin 114 extending between spaced ears I16 joined to the lower extremity of the piston rod of a hydraulic ram 118. The cylinder portion 11811 of the ram I18 is connected at its opposite upper end to a short transverse shaft loosely received between ears 122 rigidly connected to the circle 26, as best shown in FIG. 5. The general disposition of the hydraulic ram 118 is upright so that when it is extended, the scarifier teeth 108 are moved downwardly into their operative full-line disposition, as shown in FIG. 4, whereas when the ram 118 is retracted, the scarifier teeth 108 are, in turn, moved to their upper inoperative dispositions. A suitable valve (not shown) under the operator's control enables appropriate delivery of hydraulic fluid to the hydraulic rams I18 enabling the requisite extension or retraction thereof.

Since the scarifier teeth 108 are subjected to considerable and variant resistance during operation, it is preferred to provide means for limiting the pivotal motion of the lower portion of the scarifier unit 32 beyond the operative disposition, shown in full lines in FIG. 4, and such means can conveniently take the form of a rigid stop 124 mounted on each of the mounting arms I00 and adapted for engagement by a stop arm 126 projecting from the transverse beam adjacent opposite ends thereof. The disposition of the stop arm 126 is such that it engages the top of the stop 124 when the teeth 108 have reached their operative disposition, as shown in full lines in FIG. 4, and thus further pivotal motion of the lower portion of the scarifier unit 32 is precluded. Preferably, the hydraulic ram 118 is arranged so as to not reach its fully extended disposition when the stop 124 has been engaged wherefore if hydraulic pressure to extend the ram is maintained, the scarifier unit 32 is clamped against the stop 124 in its lower operative disposition by such continued pressure and the scarifier teeth 108 are accordingly rigidly held in their operative dispositions regardless of the material encountered. However, since the normal earth resistance operates in a manner tending to move the teeth 108 about the pivot shaft 102 is a clockwise direction, as viewed in FIG. 4, the rigid stop I24 opposes such motion and no strain whatsoever is placed on the hydraulic rams US.

It will be observed that whether the motor grader is being operated to utilize the blade 30 or the scarifier unit 32, all of the automatic control mechanisms, as described in the mentioned US. Pat. No. 3,346,976, can be utilized, only a slight (6 inch) adjustment in height being necessary to accommodate the lower operative disposition of the scarifier teeth 108. Additionally. each working implement, the blade 30, or the scarifier unit 32 can, of course, partake of angular motion about the vertical axis defined by the mounting circle 26 and, in the case of the scarifier teeth [08, such changed dispositions permits. in effect, a variance in the lateral spaced disposition of the teeth, themselves. Furthermore, once an adjusted disposition has been obtained. the circle 26, itself, can be clamped rigidly by the circle clamping mechanism described, thus to provide a rigid mounting for either the blade 30 or the scarifier unit 32 in its adjusted disposition. Finally, in view of the stop arrangement for the scarifier unit 32 together with the continued clamping pressure applied by the hydraulic rams [[8, the scarifier unit itself is rigidly mounted dun ing its operation so that its level can be precisely maintained. thus to enable the operator to perform the scarifing operation at the precisely desired level under the control of the automatic height and transverse slope mechanisms. described in detail in US. Pat. No. 3.346976, wherefore no further treatment of the scarfiied earth, such as compaction, is required.

Whether the blade 30 or scarified 32 be used, since they are both mounted from the circle 26, a substantially central disposition relative to machine movement is achieved. Therefore. any vertical loads are balanced longitudinally of the machine, and the requisite precision of the automatic operation is assured.

It will be apparent that various modifications and/or alterations in the structure, as described, can be made without departing from the spirit of the invention and its ready adaptibility to working implements other than the blade 30 or the scarifier unit 32 is certainly possible. Accordingly, the foregoing description of one embodiment of the invention is to be considered as purely examplary and not in a limiting sense, and the actual scope of the invention is to be indicated only by reference to the appended claims.

What is claimed is:

l. A road building machine which comprises a mobile frame,

support means mounted from said frame for adjustment,

means connected between said adjustable support means and said frame for clamping said adjustable support means in its adjusted position relative to said frame,

a first working implement,

means adjustably mounting said first working implement from said support means,

means including extensible links connected between said support means and said first working implement operable to adjust the latter.

a second working implement,

separate means adjustably mounting said second working implement from said support means,

separate means including extensible links connected between said support means and said second working implement operable to adjust the latter,

a fixed stop connected to said support means and engaged by said second implement to preclude motion of said second implement in response to operative engagement with the material being worked thereby,

said separate adjustment means being operative to move said second implement away from said stop to its inoperative disposition and towards said stop to effect clamping of said second implement thereagainst,

said first and second implements being supported for movement in unison with said support means and for independent movement with respect to each other and with respect to said support means by adjustment of said separate adjustment means.

2. A road building machine according to claim 1 wherein,

said first implement is a scraper blade and,

said second implement is a scarifier, and

said separate adjustable mounting means mounts said scarifier behind said blade for movement between an operative position wherein its ground--engaging teeth are below the lower edge of said scraper blade and an inoperative position wherein its teeth are above the lower edge of said scraper blade.

i i t 

1. A road building machine which comprises a mobile frame, support means mounted from said frame for adjustment, means connected between said adjustable support means and said frame for clamping said adjustable support means in its adjusted position relative to said frame, a first working implement, means adjustably mounting said first working implement from said support means, means including extensible links connected between said support means and said first working implement operable to adjust the latter, a second working implement, separate means adjustably mounting said second working implement from said support means, separate means including extensible links connected between said support means and said second working implement operable to adjust the latter, a fixed stop connected to said support means and engaged by said second implement to preclude motion of said second implement in response to operative engagement with the material being worked thereby, said separate adjustment means being operative to move said second implement away from said stop to its inoperative disposition and towards said stop to effect clamping of said second implement thereagainst, said first and second implements being supported for movement in unison with said support means and for independent movement with respect to each other and with respect to said support means by adjustment of said separate adjustment means.
 2. A road building machine according to claim 1 wherein, said first implement is a scraper blade and, said second implement is a scarifier, and said separate adjustable mounting means mounts said scarifier behind said blade for movement between an operative position wherein its ground--engaging teeth are below the lower edge of said scraper blade and an inoperative position wherein its teeth are above the lower edge of said scraper blade. 